Dear Lifehacker,
I know I should securely wipe my hard drive before I sell it, but is there anything else I should do before I put it up on eBay? I want to make the transition as smooth as possible.

Sincerely,
Selling it All

Dear SA,
Selling (or giving away) an old computer is often a little scary. You likely invested a lot of hours into using your computer, and it's packed full of all your personal stuff. You also want to make sure it's in tip-top running condition before you sell it off so you can get the most money. Here's what you need to do.

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If you're going to go a little while between computers, a cloud backup solution like Crashplan might be a good bet, and it's very easy to back up and restore your data. Regardless of what method you choose, make sure you run the backup before you do anything else so all your files are up to date.

Likewise, it might be a good time to clean up the services you enabled two-factor authentication on. While the chances of someone having your password after you securely delete your hard drive in the next step is slim, it's a good idea to make the process of someone logging into your accounts impossible from the start.

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Step 3: Securely Format Your Hard Drive

As we've mentioned before, the only secure way to clean out your computer's hard drive is to format it so you start from scratch. This process is time-consuming, but it's necessary before you sell your computer to stranger. You don't want any personal information remaining on the hard drive.

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Step 4: Reinstall the Operating System

Once your hard drive is formatted, you won't have anything on it. This means you need to reinstall an operating system before you sell it. The process is easy provided you still have your operating system discs. Reboot the system, and boot from the OS disc itself. Windows should automatically boot from the disc, but if not you can change the settings in your BIOS to make it work. For Mac, hold down the Option key after you hear the startup chime and select your boot disc (the USB or DVD you made yourself in step two).

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Once you're done reinstalling the operating system, it's up to you how far into the setup process you want to go. If you're selling a computer online at a site like eBay, you can stop at the new user creation screen. Just power off your computer when it asks your to create a user account and you're good to go. If you're selling on Craigslist, you might want to create a dummy user account so you can show the person buying the computer that it works.

You don't need to worry about registering the software or anything else, but if you have to prove the computer is in good working shape, just create an account with a simple username and passwords (admin/password works), and tell them to delete the account once they decide to buy.

Step 5: Clean it Up

Finally, clean up the computer and make it as nice as possible before you sell it. Not only will it likely sell for more if it looks good, it might also run a little smoother. As we've talked about before, you should do a few simple things: wipe down the computer, clean out the keyboard, clean the screen, and pop it open to clean out dust from the inside. This makes the computer a lot more aesthetically appealing, and that makes it easier to sell.